Parents are typically aware that sufficient sleep is an essential ingredient for the healthy growth and development of their toddlers. However, new research has revealed that daytime naps are also an important part of a young child's upbringing, and failure to have enough of them could result in an unhappy child. In a study conducted by the University of Colorado Boulder, published this month (January 3rd), the emotional expressions of healthy, nap-deprived toddlers were studied an hour after they missed their scheduled nap. Then were studied again on a different day after they were allowed their scheduled nap, and the findings were compared. The results showed that only one nap needs to be missed to impact on the cheerfulness of children aged between two and a half and three years old. Toddlers who didn't get enough time in their children's bunk beds exhibited "more anxiety, less joy and interest and a poorer understanding of how to solve problems." CU-Boulder assistant and leader of the study Professor Monique LeBourgeois said of the findings: "[I]nsufficient sleep in the form of missing a nap taxes the way toddlers express different feelings, and, over time, may shape their developing emotional brains and put them at risk for lifelong, mood-related problems."